Deciphering how the brain’s circuitry produces thought and behavior is an ambitious and enticing goal on the scale of the Apollo Program or the Human Genome Project. But the neuroscientists involved in a new federal effort have many challenges ahead.

The United States, China, Russia, Brazil, India, Germany and the United Kingdom are responsible for more than 60 percent of the 0.74 degree Celsius rise in global average temperature observed from 1906 to 2005.